Devices that deliver energy to walls are often utilized to treat medical conditions. One such condition is, chronic obstructive pulmonary disease (COPD), which is a progressive disease that can cause obstruction in a lung airway limiting airflow into and out of the lung. Hence, a patient suffering from COPD may have difficulty breathing. There may be a number of factors responsible for COPD, such as smooth muscle contraction, excessive mucus production, thickening of the airway wall due to inflammation, and alteration of structures around the airway. More particularly, excessive and inappropriate constriction of airway smooth muscle (ASM) located within the walls of lung airways of such patients may be a contributory factor for COPD. Thus, reducing excessive ASM can provide a therapeutic benefit for treating COPD. Minimally invasive techniques have been developed to successfully reduce and/or eliminate excessive ASM.
An example of a minimally invasive technique for reducing (e.g., shrinking or debulking) excessive ASM involves delivery of thermal energy to the airway wall using a catheter. To apply the treatment, the catheter is positioned at a desired location within the airway. An electrode array at the tip of the catheter is expanded to contact the airway wall. The electrodes are expanded manually by squeezing a handle of the catheter to the desired expansion amount. In some embodiments, the treatment may involve damaging nerve tissue in airways of the pulmonary system to reduce the resting tone of smooth muscle tissue.
The use of conventional minimally invasive techniques may still be suboptimal. For example, it is possible to over-expand the electrodes by squeezing too much on the handle, leading to possible damage of the electrodes and adjacent body tissue. In addition, a user may not apply enough pressure to the handle, resulting in the electrodes not contacting or delivering thermal energy uniformly to the airway wall.
Thus, there are still shortcomings related to the known minimally invasive techniques utilized to reduce at least one symptom of COPD.